Compressor shaft seal



COMPRESSOR SHAFT SE AL Filed June 28, 1940 2 Sheets-Sheet 1 VII.

A; ATTORNEY July 21, 1942.

c. E. PLOEGER 2,290,813 COMPRESSOR SHAFT SEAL Filed June 28, 1940 2 Sheets-Sheet 2 .u I J 32 43 44 1\ W I f F h 68 s 63 62 78 77 76 i hmn."a.

55 Q w I Patented July 21, 1942' COMPRESSOR SHAFT SEAL Clyde Edward Ploeger, Evansville, Ind., assignor to Servel, Inc., New York, N. Y., a corporation of Delaware Application June 28, 1940, Serial No. 342,887

2 Claims. (01. 308-351) elevation, and embodying the invention;

Fig. 2 is a section taken on line 22 of Fig. 1'; Fig. 3 is a section taken on line 3-3 of Fig. 2, and showing details of a rotary oil pump constituting part of the shaft lubricating system;

Fig. 4 is a section taken on line 44 of Fig. 3; and

Fig. 5 is a detail sectional view of part of the compressor'shown in Fig. 2.

A compressor III is a four-cylinder V type, with Also formed in the end wall section H of the crankcase I2 is an inlet port .40- communicating with the pump chamber 34 on one side of the blade 31, and supplied with oil from the lower cylinder blocks mounted at a 90 angle. In a crankcase |2 below the cylinder blocks H is a crankshaft l3 journalled in the bearing sections l4 and I5 of the respective, end walls l5 and of said case. A pair of spaced eccentrics l3, formed with counterweights' 20 are secured on shaft'"|3. Pistons in one cylinder block H are connected to the eccentric cranks It by master connecting rods 2|. Pistons in the other block are connected to straps I! of the master rods 2| by articulated rods 22. A belt pulley or sheave 23 is secured on-the end of shaft l3 outside of thecasing.

The main lubricating system comprises a rotary pump 23 at one endof shaft i3 which forces oil under pressure through an axial bore 23 in the shaft 3, and then through; radial bores 35' to the eccentric surfaces andthe shaft bearing opposite the pulley end. The crankcase I2 is filled with oil to a level high enough to immerse the lowersect'ion's of the eccentric cranks so that cylinders and pins are oiled by splash.

oil sump section of the crankcase through a pipe 4|. Communicating with the pump chamber 34 on the other side of the blade 31 is a discharge port 42 communicating with the central shaft bore 23 through a channel 43 formed in an end closure plate 44 of the pump 28.

Oil which enters space 35 through the inlet port 40 is displaced clockwise in said space by the rolling action of the ring 33 toward the discharge port 42. From discharge port 42, the oil travels through the channel 43 of the closure plate 44 and into the open end of the shaft bore 29. The oil under pressure travels along this central bore 25, and is distributed therefrom to the said shaft and eccentric bearings through the radial ducts 30.

At the pulley end of shaft I3, the bearing section I 5 of the end case wall H is provided with a hole 50 into which is fitted a bearing sleeve 5| for said shaft. This hole 50 is enlarged at its outer end 52 to afford an annular shoulder 53, against which abuts an annular flange 54 on the bearing sleeve 5|. The end section of the bearing sleeve"5| beyond its flange 54 is reduced to form an annular rim or projection 55. A gasket or packing ring 55 sealably embraces this sleeve rim 55, and is clamped-between the sleeve flange 54 and an annular seal nose 51. The seal nose 51 seatsin the end case section, l5on the gasket 55, and extends outward into contact with a seal ring" loosely encircling the shaft l3- The contact faces of the seal nose 51 and seal ring 5| are ground for perfect sealing contact, and are formed on annular end projections or bosses 52 The oil pump 25 may be of any suitable construction, but merely as an example it is shown comprising an eccentric 32 keyed to the shaft l3, and ring 33 joumalled on eccentric 32 in a circular pump chamber 34. Pump chamber 34 is a recess in the end wall section l4 of the crankcase, and is concentric with the crank shaft II. The ring 33 is positioned to tangentially contact and roll on the periphery of the pump chamber 34. A radial blade 31 on the ring 33 projects into a slot formed in a disc 38 journalled in the end wall section- I4 0! the case l2.

and 53 of said seal rings respectively.

The seal ring 5| is yieldably urged into sealing contact with the seal nose 51' by a compression coil spring 54. encircling the shaft I3 and having one endabutting the seal. ring 5| and the other end abutting a spring retaining disc 55. Disc 55 is held by a nut threaded onto a reduced section 51 of the shaft l3 which makes a shoulder 53 against which is thrust a disc 10, sealed against said shoulder by a packing ring 1|.

Between the sealing ring 61 and the disc 10 is a Sylphon bellows 13 encircling said shaft within the coil spring 54. The ends of the bellows 13 are connected respectively to the ring 5| and disc 10 by welding, brazing, soldering or any suitable means which will producea fluid tight Joint.

The clearance between the two rings 51 and 5| rings 51 and SI.

The balanced pressure sealing device above described is disposed on the outside of the crankcase l2 between said crankcase and the pulley 23.

-When the pulley 23 is slipped 6n the end of the shaft l2, the whole sealing device is immediately accessible for ready removal, without the necessity of demounting any part of the crankcase l2.

The seal nose 51 extends outward beyond the crankcase H to permit its easy removal for regrinding or replacement purposes.

To keep the seal cool, the shaft l3 has a duct 16 extending radially from the central oil bore 29 into the bellows 13. The bearing sleeve 5| is provided with a groove 11, extending along the inner face thereof, and communicating with the interior of the bellows 13 through the annular clearances 18 and 19, formed between the two seal rings 51 and GI and the periphery of the shaft l3. With this construction, the lubricating oil delivered under pressure from the oilpump 28 through the central shaft bore 29 travels through the radial' duct 16 into the bellows I3 to fill said bellows. The oil returns along the annular clearances I9 and 18 within the seal rings 6| and 51, and then into the groove 11 to lubricate the bearing 5|. The oil discharges from the bearing into the oil sump in the crankcase l 2.

Various changes and modifications may be made within the scope of this invention as set forth in the following claims;

aaoaaia What is claimedis:

1. In a compressor having a crankcase, a crankshaft jutting through a wall of said case, and a bearing for said shaft in said wall, said bearing providing for flow of lubricating oil therethrough; a shaft seal comprising a first seal ring resiliently sealed in fluid tight relation in the outside of said wall around and spaced from said shaft, a second seal ring also around and spaced from said shaft outside said wall and revolubly engaging said first seal ring in sealing contact, a bellows having one end connected in fluid tight engagement with said second seal ring and the other end similarly connected. to said shaft by a removable connection, the spaces around said shaft within said bellows and seal rings being in communication with each other and with said bearing, said shaft having a passage leading to the space between said shaft and said bellows, and an oil pump connected to withdraw oil from said crankcase and force the oil through said passage whence it flows in the spaces around said shaft within said bellows and seal rings and then through said bearing back to the crankcase.

2. In a compressor having a crankcase and a crankshaft jutting through a wall of said case; a bellows type shaft seal including a bellows, revoluble seal ring, and stationaryseal ring, all removable by withdrawal over the end of said shaft outside said case, there being spaces around said shaft within said bellows and seal rings which spaces are in communication with each other and with said crankcase, said shaft having a passage leading to the space around the shaft within said bellows, and an oil pump connected to withdraw oil from said crankcase- :ind force the oil through said passage whence it iiows in said spaces around said shaft within said bellows and seal rings and then back to the crankcase.

CLYDE EDWARD PLOEGER. 

